1. Field of the Invention
The present invention relates to an electric motor and a manufacturing process thereof.
2. Description of the Related Art
An electric motor for rotating a rotor requires a balance of the rotor with high precision. For example, if the center of gravity of the rotor is shifted from a rotational axis, the electric motor generates vibration during rotational movement of the rotor, resulting in an unstable operation. JP-B-3621929 has proposed a method for adjusting a balance of the rotor.
There is a need for an electric motor which allows a balance of a rotor to be adjusted in a simple way and a process for manufacturing such an electric motor.